LONDON (AP) -- With their offense on a hiatus early, the U.S. women turned up the defensive pressure and cruised into the semifinals of the Olympic basketball tournament.

Diana Taurasi scored 15 points and Candace Parker added 12 to lead the Americans to a 91-48 rout of Canada on Tuesday and advanced to the semifinals for the eighth straight time.

While the four-time defending gold medalists had their way on offense in their last game - a 114-66 rout of China - they were sloppy early on against Canada.

It was the defense that got the U.S. going - the Americans forced 26 turnovers.

"We get steals. We get deflections. We get rebounds, kick the ball out and here we go. We're rolling." said U.S. forward Tamika Catchings.

The U.S. held Canada to the fewest points it has given up in an Olympic quarterfinals since beating Slovakia 58-43 in 2000.

Next up for the U.S. in the semifinals on Thursday is a meeting with the winner of the Australia-China game.

The Americans haven't lost to Canada since playing in the world championship in 1975. The victory was their 39th straight in Olympic play and came 20 years to the day after the win that started the streak - a 88-74 victory over Cuba for the bronze medal in the 1992 Barcelona Games.

Canada, which was the final team to qualify for the London Games, made its first appearance in the Olympic quarterfinals since finishing fourth at the 1984 Los Angeles Games. The Canadians looked timid against the Americans' pressure defense at the start. The U.S. forced Canada into three 24-second shotclock violations in the first seven minutes.

"That's probably a better feeling than making a 3, when as a unit you found a way to stop them as a unit," Taurasi said. "That's really hard to do because to get a shot off isn't the hardest thing, it might not be a quality one, but you can get a shot off."

There could have been a few more as Canada tried to work the clock down on every offensive possession and the U.S. forced them into off-balanced shots that barely hit the rim.

Taurasi said locking teams up defensively "has to be our focus."

Despite its stellar defense, the U.S. was sloppy on offense.

The Americans missed seven of their first nine shots and only led 8-4 before scoring the next 11 points to take control. Parker had four points during the spurt.

Canada was able to close within 11 points in the second quarter, but the U.S. put the game away, outscoring its northern neighbors by eight the rest of the half to lead 42-21 at the break.

Shona Thorburn's running left-handed fling from 15-feet that banked in at the halftime buzzer was the lone highlight for Canada in the first half - when the Canadians had more turnovers (12) than field goals (six).

By the time Kobe Bryant, LeBron James and Kevin Durant showed up in the third quarter after they had finished practice, the U.S. women had doubled Canada's score - 57-28.

It only got worse from there.

Sylvia Fowles played in her second straight game after missing three in a row to rest a sore left foot. She only played nine minutes in the win over China. She looked stronger against Canada scoring 12 points in 9 minutes.